Multiple methods have been suggested, in the literature, to compute the terminal voltage of the cell. Here we focus on the works of Marquis et al. [1]} and Richardson et al. [2]}, which both show very good agreement to solutions of the DFN model. We describe their results in what follows. In both cases the terminal voltage \(V(t)\)  can be written in the form
\(V(t) = U_\mathrm {eq} - \eta _\mathrm {r} - \eta _\mathrm {c} - \Delta \phi _\mathrm {e}- \Delta \phi _\mathrm {s},\) 
